Spelling, and getting rid of unnecessary complications.

modules/Bio/EnsEMBL/DBSQL/DnaAlignFeatureAdaptor.pm

@@ -488,7 +488,7 @@ FEATURE:
     }
 
     # If a destination slice was provided, convert the coords.  If the
-    # dest_slice starts at 1 and is foward strand, nothing needs doing.
+    # dest_slice starts at 1 and is forward strand, nothing needs doing.
     if ( defined($dest_slice) ) {
       if ( $dest_slice_start != 1 || $dest_slice_strand != 1 ) {
         if ( $dest_slice_strand == 1 ) {
@@ -498,7 +498,7 @@ FEATURE:
           my $tmp_seq_region_start = $seq_region_start;
           $seq_region_start = $dest_slice_end - $seq_region_end + 1;
           $seq_region_end = $dest_slice_end - $tmp_seq_region_start + 1;
-          $seq_region_strand *= -1;
+          $seq_region_strand = -$seq_region_strand;
         }
 
         # Throw away features off the end of the requested slice.